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1.
The intramolecular cyclization of the tertiary amines (3) with potassium amide in liquid ammonia affords a variety of unsymmetrical isoindolines (5) and isoindoles (6).  相似文献   

2.
A one-pot conversion of isoindolines to 1-arylisoindoles was established from palladium-catalyzed cascade C-H transformations, that is, the dehydrogenation of isoindolines to give isoindoles, with subsequent C-H arylation of the isoindoles.  相似文献   

3.
Substituted 1,3-dihydro-2H-isoindoles (2, isoindolines) were prepared and subjected to palladium-catalyzed formate reduction. Alkyl isoindolines were reduced to 4,5,6,7-tetrahydro-2H-isoindoles (1). Only partial reduction was observed for 5-methoxyisoindoline, and 4-methoxy-, 5-carbomethoxy-, amino-, and amidoisoindolines were inert to the reaction. Halogen-substituted isoindolines were dehalogenated and reduced to 4,5,6,7-tetrahydro-2H-isoindoles. Isoindole 24 was also reduced to a mixture of an isoindoline and a 4,5,6,7-tetrahydro-2H-isoindole. In contrast, 2,3-dihydro-1H-indoles 21 underwent dehydrogenation to give thermodynamically stable indoles. Theoretical calculations show the significant difference in aromaticity between isoindoles and indoles, corresponding to the observed differences in reactivities. Tetrahydro-2H-isoindoles 1 were oxidized to 4,5,6,7-tetrahydroisoindole-1,3-diones in the presence of NBS and air.  相似文献   

4.
A catalytic enantioselective method for the synthesis of chiral 1H‐isoindoles bearing quaternary stereogenic centers is reported. Powered by readily accessible phosphordiamidite ligands, the presented palladium(0)‐catalyzed C?H functionalization uses trifluoroacetimidoyl chlorides as electrophilic components. It delivers previously inaccessible perfluoroalkylated 1H‐isoindoles in high yields and enantioselectivities. The subsequent diastereoselective addition of nucleophiles provides access to densely substituted and sterically hindered isoindolines.  相似文献   

5.
《Tetrahedron》2019,75(33):4626-4631
A new efficient and diastereoselective synthesis of multisubstituted isoindolines with two stereogenic centers via sequential Ugi/aza-Michael addition reaction was developed. Ugi-3CR of aldehydes 1, amines 2 and isocyanates 3 in the presence of catalytic amount of H3PO4 produced intermediates 4, which were then transformed to isoindolines 5 with good 1,3-trans diastereoselectivity in the presence of K2CO3 by intramolecular aza-Michael addition. Sequential Ugi-azide and aza-Michael addition reaction of aldehydes 1, amines 2 and trimethylsilyl azide 6 also produced 4-tetrazolyl substituted isoindolines 8 with good 1,3-trans diastereoselectivity in the presence of potassium carbonate.  相似文献   

6.
A facile and microwave accelerated reaction of 1-chloro-3-(4-chlorophenyl)isoquinoline with various heterocyclic amines, catalyzed by Pd, in the presence of BINAP additive and sodium carbonate as the base, leads to the formation of 3-(4-chlorophenyl)-1-(1H-1,2,3-triazol-1-yl)isoquinoline, 3-(4-chlorophenyl)-1-(1H-imidazol-1-yl)isoquinoline and 3-(4-chlorophenyl)-1-(1H-1,2,4-triazol-1-yl)isoquinoline via Buchwald protocol in good yields. Similarly pyrazolylisoquinolines are also reported.  相似文献   

7.
Covalent attachment of a 1,2,4-triazole iridium complex to mesoporous MCM-41 generated a heterogeneous catalyst that was found to be effective in the synthesis of 2-aryl isoindolines, quinolines, cyclic amines, and symmetrical secondary amines through a cascade borrowing hydrogen strategy. Interestingly, the supported heterogeneous iridium catalyst prepared from the 1,2,4-triazole iridium complex and mesoporous MCM-41 exhibited high catalytic activity in the preparation of 2-aryl isoindoline derivatives and symmetrical secondary amines. The catalyst system is highly recyclable for at least five times. Besides the important effect of the triazole, iridium sites grafted on siliceous supports can act as multifunctional catalytic centers and thus greatly enhance the catalytic activity of the catalysts. Furthermore, mechanistic experiments revealed that the reaction is initiated by an initial alcohol dehydrogenation and promoted by an iridium hydride intermediate. Importantly, the direct detection of a diagnostic iridium hydride signal confirmed that the synthesis of 2-aryl isoindolines occurs by a borrowing hydrogen process. This work provides an efficient example of isoindolines synthesis through a borrowing hydrogen strategy.  相似文献   

8.
A simple and highly efficient one-pot, three-component synthesis of 3-(2-(4-chlorophenylimino)-3-(4-chlorophenyl)-2,3-dihydrothiazol-4-yl)-2H-chromen-2-ones has been reported by the reaction of 3-(2-bromoacetyl)-2H-chromen-2-one, primary amines, and phenyl isothiocyanates in presence of dimethylformamide as a solvent. The structures of newly synthesized compounds were confirmed by their analytical and spectral data.  相似文献   

9.
The reaction of 5-(4-chlorophenyl)-4-benzoyl-1-(4-hydroxyphenyl)-3-hydroxy-3-pyrrolin-2-one with aromatic amines affords the corresponding 3-arylamino derivatives, and the reactions of 5-aryl-4-acetyl-1-(4-hydroxyphenyl)-3-hydroxy-3-pyrrolin-2-ones with p-toluidine yield 5-aryl-4-(1-p-tolylamino)ethylene-1-(4-hydroxyphenyl)pyrrolidin-2,3-diones.  相似文献   

10.
Aminomethylation of 3,5-dicyano-6-oxo-1,4,5,6-tetrahydropyridine-2-thiolates upon treatment with primary amines and excess formaldehyde leads to 3,7-diazabicyclo[3.3.1]nonane derivatives. N-Methylmorpholinium 4-(2-chlorophenyl)-3,5-dicyano-6-oxo-1,4,5,6-tetrahydropyridine-2-thiolate was obtained by the reaction of (E)-3-(2-chlorophenyl)-2-cyanoprop-2-enethioamide with 1-cyanoacetyl-3,5-dimethylpyrazole and N-methylmorpholine in acetone in quantitative yield. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2397–2400, December, 2007.  相似文献   

11.
Novel N-acylated-(S)-cysteine derivative-N-(R)-mandelyl-(S)-cysteine (R-NMC), containing additional chiral center, aromatic and polar alpha-substituents in contrast to the traditionally used enantiomerically pure thiols, has been demonstrated to be an efficient SH-reagent for enantiomeric HPLC analysis of primary nonfunctionalized amines and amino alcohols after precolumn derivatization with o-phthalaldehyde. The R-NMC-derived isoindoles as well as adducts formed using traditional SH-reagents had a characteristic absorption maximum at 340 nm with a molar absorbance 6000 M(-1) cm(-1), were stable during the HPLC-analysis and highly fluorescent allowing to detect 1 fmol of amino compound. Using diastereomeric R-NMC all tested amino alcohols were resolved effectively as well as nonfunctionalized amines, some of which were not resolved by a direct method on a chiral phase. Applying traditional enantiomeric N-acetyl-(S)-cysteine (NAC) only some isoindoles formed by aliphatic amino alcohols have been separated satisfactorily. The enhanced selectivity for R-NMC-derived isomers has been achieved, obviously, due to the involvement of the substituents at an extra chiral center into additional intramolecular interactions.  相似文献   

12.
2-Alkyl-1(2-formylphenyl-N-alkyliminomethyl)isoindoles were prepared by the reaction of o-phthaldehyde with primary amines in 99% ethanol at 0°. 2-Alkyl-3-alkyliminoisoindolinones were isolated from the reaction mixture as by-products. Their formation mechanism is proposed.  相似文献   

13.
冯菊红  丁涛  荣霞  龚昕  巨修练 《合成化学》2016,24(7):561-564
以三聚氯氰为原料,依次与取代胺和恶霉灵经逐级取代反应合成了17个新型的含异恶唑环的1,3,5-三嗪类衍生物(3a~3q),其结构经1H NMR和ESI-MS表征。抗真菌活性测试结果表明:在用药量为300 μg·mL-1时,2-(5-甲基异恶唑基-3)-氧基-4-(邻氯苯胺基)-6-氯-1,3,5-三嗪(3l )对禾谷镰刀病菌的抑制率为65%。  相似文献   

14.
The reaction of 2-(2 pyridytcarbonyl)benzoic acid with thionyl chloride affords an unexpected product of the intramolecular acylation of the pyridine nitrogen atom, namely, 6,11-dioxo-6,11-dihydrobenzo[blquinotizinium chloride. At the same time, 2-(2-quinotylcarbonyl)benzoic acid forms the expected cyclic acid chloride, namely, 3-(2-gitinotyl)-3-chlorophthalide in this reaction. Both compounds acylate ammonia and primary amines, including those with bulky alkyl groups (tert-butyl, 1-adamantyl, and 1,1,3,3-tetramethylbutyl) with the formation of 2-R-3-hydroxy-3-(2pyridyl- or 2-quinolyl)isoindolines. The protonation of the pyridine nitrogen atom of N-(1,1,3,3-tetramethylbutyl)-2-(2pyridylcarbonyl)benzamide, obtained in the open amide form, is accompanied by the closing of the isoindotinone ring; the deprotonation is accompanied by ring opening.Riga Technical University, Riga LV-1048. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 499–504, April, 1994. Original article submitted March 17, 1994.  相似文献   

15.
A synthesis of benzo[f]isoindole-4,9-diones 1 is presented starting from the reaction of 2,3-bis(bromomethyl)-1,4-dimethoxynaphthalene 15 with primary amines affording 2,3-bis(aminomethyl)-1,4-dimethoxynaphthalenes 14, which could be converted by CAN-mediated oxidation in one step to benzo[f]isoindole-4,9-diones 1. An alternative synthesis of benzo[f]isoindole-4,9-diones 1 starts from 2,3-bis(bromomethyl)-1,4-naphthoquinone 9 via 2,3-dihydrobenzo[f]isoindoles 10 which spontaneously oxidize.  相似文献   

16.
Starting from 4-chlorobenzoic acid, 10 new 5-(4-chlorophenyl)-N-substituted-N-1,3,4-thiadiazole-2-sulfonamide derivatives were synthesized in six-steps. Esterification of 4-chlorobenzoic acid with methanol and subsequent hydrazination, salt formation and cyclization afforded 5-(4-chlorophen-yl)-1,3,4-thiadiazole-2-thiol (5). Conversion of this intermediate into sulfonyl chloride 6, followed by nucleophilic attack of the amines gave the title sulfonamides 7a-7j whose structures were confirmed by NMR, IR and elemental analysis. The bioassay tests showed that compounds 7b and 7i possessed certain anti-tobacco mosaic virus activity.  相似文献   

17.
合成了6种1-取代-4,5-二(4-氯苯基)咪唑.以对氯苯乙酸和氯苯为原料,经Friedel-Crafts酰基化反应、二氧化锡氧化、与多聚甲醛和乙酸铵环合制备了中间体4,5-二(4-氯苯基)咪唑(5),5再经取代得到3个1-取代-4,5-二-(4-氯苯基)咪唑类化合物6a-c.6a再分别与液体胺经亲核取代反应得到3个1-取代乙酰胺类-4,5-二-(4-氯苯基)咪唑类化合物7a-c.目标化合物结构用核磁共振氢谱和红外光谱进行了表征.  相似文献   

18.
Oxidation of 3-amino-4-(4-chlorophenyl)furazan ( 1 ) and its phosphine imine derivative, 3-(4-chlorophenyl)-4-trioctylphosphiniminofurazan ( 3 ), with dimethyldioxirane (DMD) gave 3-(4-chlorophenyl)-4-nitrofurazan ( 4 ) as the exclusive product. However, the sulfilimine derivative, 3-(4-chlorophenyl)-4-dimethylsulfiliminofurazan ( 2 ), was converted by DMD to the sulfoximine, 3-(4-chlorophenyl)-4-dimethylsulfoximinofurazan ( 6 ). These results contrast dramatically with the oxidations of these compounds with peracids.  相似文献   

19.
During vacuum distillation of 3-(dialkylamino) derivatives of 1,4-diphenyl- and 4-phenyl-1-(p-chlorophenyl) hex-5-en-1-ynes deamination occurs resulting in a high yield of p-diarylbenzenes. The amines transformation into terbenzenes is a domino-reaction: first step consists in the β-elimination of secondary amines with the generation of conjugated dienyne which via an electrocyclic reaction transforms into cyclic allene intermediate. The latter after 1,3- or 1,5-hydride shift quickly converts into the final reaction products.  相似文献   

20.
本实验合成了一种共反应剂N,N,N’,N’-4-丙基-戊二胺(TPPD),它的分子中含有两个叔氨基,与传统的共反应剂三丙胺(TPA)相比增加了一个氮的活性位点。并且分子中的碳碳长链使得TPPD的疏水性增加,因此能与钌配合物[Ru(bpy)3][4-(Clph)4B]2同时固定到ITO电极上,减少了ECL过程中的共反应剂的消耗。  相似文献   

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